The kiss was regarded as the introduction, as it were, to matrimonial cohabitation—initium consummationis nuptiarum; it was symbolical of marriage—viri et mulieris conjunctio. Certain ancient jurists have even discussed the question whether a married woman who has suffered herself to be kissed by a stranger has not thereby rendered herself guilty of adultery.
The decree of the Roman law which, so far as I know, still partly holds good in Greece, is met with again in the Latin countries during the Middle Ages. It was incorporated in the law of the Visigoths (Lex Romana Visigothorum), and migrated thence to the different old Spanish fueros and the old French law, in which the word osculum was also used in the learned form oscle. It was likewise admitted into the law of the Lombards, and Italy is most probably the West European country where donatio propter osculum has been longest retained. We find, even down to our own times, traces of the same in customary laws.
This is probably the only ceremonial kiss that has received legal sanction; but wherever elsewhere we may turn our eyes and investigate old ceremonies, we constantly find the kiss a necessary and important part.